HP 8566B Adjustment Manual page 298

17. 20/30 Loop Phase Lock Adjustments
3-l 56 Adjustments
12. Set the controls of the second spectrum analyzer as follows:
CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 MHz
FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 MHz
REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -14 dBm
MARKER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (j-j
Adjustment AlOA4Lll PLL3 VCO ADJ is sealed at
normally does not require readjustment unless a component failure
has occurred. AlOA4Lll PLL3 VCO ADJ should be adjusted with
the metal shield installed over the PLL3 VCO on AlOA4 PLL3 Up
Converter Assembly.
13. A 166 MHz signal should be centered on the display of the second
spectrum analyzer, indicating that PLL3 is phaselocked. If not,
coarse adjust AlOA4Lll PLL3 VCO ADJ to center the signal
displayed on the second spectrum analyzer and phaselock PLL3.
14. With PLL3 phaselocked, readjust AlOA4Lll PLL3 VCO ADJ as
necessary for a DVM indication of -7.0 f 0.1 Vdc.
the
15. On RF Section, key in
[ ]
0 , S
FREQUENCY SPAN
HZ
The DVM indication should be -3.5 f 0.6 Vdc.
16. On the RF Section, key in
(
MHz,
FREQUENCY SPAN
( ).
CLEARWRITE
17. Set the controls of the second spectrum analyzer as follows:
CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164.001 MHz
FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 MHz
REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . -14 dBm
18. On the second spectrum analyzer, press MARKER
and verify that the output power level of the PLL3 VCO at
164.001 MHz is -20 dBm f 2 dB as indicated by the marker.
the
If it is not, note amplitude and change the values of
factory-select resistors AlOA4R29 and AlOA4R33 as necessary.
Refer to 'Iable 3-13 for a list of standard resistor values and
corresponding change in circuit gain to adjust the PLL3 VCO
output power level to -20 dBm, and to Table 3-4 for HP part
numbers.
Standard Values for AlOA4R29 and AlOA4R33
]
42.569999 MHz,
FREQUENCY
(SINGLE), AC
WEEP TR
( )
CENTER FREQUENCY
)
100 kHz, SWEEP (?iIGZ], TRACE A
Resistors
R29 R33
68.1 68.1
68.1 75
75 75
68.1 82.5
75 90.9
the factory and
E A
42.6499
[ )
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